Gone Today, Back Tomorrow June 4, 2007Posted by Mrs Weird Scientist in Genetics, Human Body, Stem Cells, Tough Stuff.
Hair follicles, that is. Scientists used to think that once a person lost their hair follicles and went bald, the follicles could never be replaced again. Nope. According to a study by some very curious scientists at the University of Pennsylvania, there’s still hope for your balding dad.
Here’s What Happens
Your head contains thousands of hair follicles and each follicle can grow a single hair. The follicles themselves are actually kinda old because they are produced by an embryo, which is the earliest stage of human development. Scientists used to think that once an embryo had produced follicles, that was it. No more follicles could be made later. So once the follicles were damaged or lost, hairless forever!
This is where a gene comes in to save the day. Your genes are something you inherit from your parents. They are a unique set of instructions that determine the color of your eyes and lots of other traits you have. Scientists at the University of Pennsylvania found a gene called Wnt. This gene not only helps wounds heal, but it can also help make new hair follicles.
So you’re maybe wondering how this new gene can help those damaged hair follicles in your bald dad? Well, lets take a look at what scientists did in the experiment. They removed little bits of the outer skin layer, also called the epidermis, in mice. Remember how I said the Wnt gene helps heal wounds and produce new hair follicles? Well, after that small piece of skin was removed from each mouse, a wound was left.
Now, two really fascinating things happened.
The first thing was that when the wound started to heal, new follicles began to grow. Did the Wnt gene do it alone? No way- something else helped. The second thing is that scientists figured out stem cells were responsible for this growth. These are very special cells found all over your body that can multiply into many more cells. When the scientists removed a little piece of skin from each mouse- creating a wound- this was like a signal for the Wnt gene to get those stem cells to wake up and start working.
But Wait, There’s More
To make sure they really had something that worked, scientists tried to block the Wnt gene. What do you think happened? If you guessed that no new hair follicles were produced, you are right! Without the Wnt gene to activate them, the stem cells didn’t create new hair follicles. And since scientists like to meddle so much, they decided to try increasing the gene’s activity. What now? If you guessed that more hair follicles were produced, you are right again.
Run That By Me One More Time?
It’s like a series of alarm clocks. The wound wakes up the Wnt gene, which then wakes up the stem cells. Those stem cells can now get busy fixing the wound and creating hair follicles. Block the Wnt gene and the stem cells won’t do their thing. Boost the Wnt gene’s power and the stem cells work overtime.
Is Dad Gonna Grow A Full Head Of Hair?
Maybe one day, but not anytime soon. Scientists still need to figure out how to safely create a wound on a bald spot and then power up the Wnt gene. For now, you can tell dad not to throw out that hairpiece just yet. Remind him it could be worse- he could be losing his teeth.
Photo Credit: George Cotsarelis, University of Pennsylvania, School of Medicine. The blue lines in the picture show copies of cells originating from stem cells. The cells move toward the middle part of the wound to heal it quickly and produce hair follicles. It looks gross but once it has healed, there’s almost no scarring and better yet, there’s hair!